STUDY OF LANTHANUM LOCAL-STRUCTURE IN MONTMORILLONITE

The local structure of the interlamellar lanthanide ions in montmorill onite upon heating is studied. The analysis of the EXAFS data has been carried out using two model environments, that of La3+ aquocomplex an d that of the lanthanum oxide. The information thus obtained is crucia l in elucidating the intercalation mechanism and demonstrates the impo rtant role that XAFS techniques can play in the knowledge of the locat ion and environment of the exchangable ions in layered silicates.